Technical Field
The present disclosure relates to an electrochemical machining apparatus for forming a turbine blade. More particularly, the present disclosure relates to a high-precision electrochemical machining apparatus which is capable of performing accurate deep cutting on a surface of the turbine blade.
Description of Related Art
As semiconductor industry, optoelectronics and biomedical industry continue to flourish, many products are developed with the trend towards ultra-precision, high-density, intelligence and miniaturization. In all related manufacturing methods, an electrochemical machining (ECM) process has the biggest edge, which is a processing technique that is relatively suitable for use in mass production with high-precision, and has the advantages that cutting tools are less likely to be worn out, workpieces to be processed are not limited by the hardness and strength of metal material, the workpieces with higher hardness can be applied, the processing speed is relatively fast, and the workpieces processed have good surface smoothness with no edge burrs generated on the edges, and have small rounded edges, etc.
When an electrochemical machining process is performed, a workpiece is first electrically connected to an anode electrode of a power source, and a machining electrode is electrically connected to a cathode electrode of the power source, and an electrolyte is enabled to flow between the workpiece and the machining electrode, thereby removing redundant material of the workpiece by a reaction between the workpiece and cathode ions generated by the cathode electrode based on an anodic dissolution principle, thus accomplishing the purpose of electrochemical machining process.
A conventional ECM apparatus includes a tank, a power supply, a machining electrode and a driving module. The tank is configured to receive a workpiece and an electrolyte. The machining electrode includes an electrode substrate having an extending length and at least one agitating structure disposed around the electrode substrate. The electrode substrate includes a first end and a second end. The second end is configured to perform electrochemical machining on the workpiece, thereby forming a machined structure thereon. The driving module moves along with the first end of the electrode substrate for displacing and rotating the electrode substrate, thereby enabling the rotated agitating structure to press and agitate the electrolyte to flow through the machined structure, thus enhancing circulation of the electrolyte in the machined structure.
When the aforementioned ECM apparatus performs electrochemical machining on a workpiece, the driving module (i.e. a feed device) has to be controlled to move the machining electrode, so as to perform electrochemical cutting on the workpiece. However, when being applied to a high-precision cutting process, the ECM process using the feed device to control a machining electrode has the following disadvantages.
1. When it is desired to perform high-precision shallow cutting on the workpiece, the driving displacement accuracy of the feed device has to be increased at the same time, thus likely increasing the tool cost, and being disadvantageous to mass processing.
2. When the feed device has been operated for a long period of time, its feeding accuracy will likely fail to meet standard tolerance due to the aging of its mechanical components thus easily causing its product to lack fidelity, and resulting in a poor yield.
In view of the foregoing, the conventional ECM process u site the feed device is not suitable for use in electrochemical machining of turbine blades that require high precision. Therefore, the present disclosure provides an ECM apparatus specifically for electrochemical machining of turbine blades. More particularly, the present disclosure relates to a high-precision ECM apparatus which is capable of performing accurate deep cutting on surfaces of the turbine blades.